If you're having trouble with your hair colour fading fast - you can always easily re-apply! Even if your hair is already coloured purple you can just reapply with the same product.
Colour will develop and last better depending on the type of hair you have. If you have very thick and long hair, we would recommend you use two packets per hair colouring session. But stick to the duration time on the colouring packet, no more than the maximum time, to avoid damaging your hair!